assertEquals(rootCause, exception.getCause().getCause());
    }

    @Test
    public void test_constructor_withSpecialCharactersInMessage() {
        // Test constructor with special characters in message
        String message = "Error with special chars: \n\t\r\"'<>&";
        SearchEngineClientException exception = new SearchEngineClientException(message);

        assertNotNull(exception);

        assertEquals(unicodeString, decoded);
    }

    @Test
    public void test_special_characters_base64_encoding() {
        // Test that special characters are properly encoded/decoded
        String specialString = "******@****.***";
        String encoded = BaseEncoding.base64().encode(specialString.getBytes(StandardCharsets.UTF_8));

     * Enable or disable popular word tracking and display.
     * When enabled, frequently searched terms are tracked and displayed.
     */
    @Size(max = 10)
    public String popularWord;

    /**
     * Character encoding to use for CSV file exports.
     * This setting affects the encoding of downloaded CSV files.
     */
    @Required
    @Size(max = 20)
    public String csvFileEncoding;

    /**

        assertTrue(item.isUpdated());
        assertFalse(item.isDeleted());
    }

    @Test
    public void test_specialCharacters() {
        // Test with special characters
        String specialInput = "test@#$%^&*()_+-=[]{}|;':\",./<>?";
        StopwordsItem item = new StopwordsItem(1, specialInput);
        assertEquals(specialInput, item.getInput());

            @Override
            public String getCanonicalLdapName(String name) {
                return name;
            }
        });
        sambaHelper.init();

        // Test with Turkish locale characters that have special lowercase rules
        assertEquals("1üser", sambaHelper.getAccountId(createMockSID(1, "Üser")));
    }

    @Test
    public void test_getAccountId_exception_handling() throws SmbException {

                        }
                    });

            assertEquals(path, provider.provideDefaultPath());
        }
    }

    // Test cipher with special characters
    @Test
    public void test_cipherWithSpecialCharacters() {
        // Create a mock cipher for testing purposes
        InvertibleCryptographer cipher = new InvertibleCryptographer("AES", "1234567890123456", null) {

        // Test with file path containing special characters
        Path tempDir = Files.createTempDirectory("test-スレッドダンプ-dir");
        Path tempFile = tempDir.resolve("thread-dump-テスト.txt");

        try {
            ThreadDumpUtil.writeThreadDump(tempFile.toString());

            assertTrue("File with special characters should be created", Files.exists(tempFile));

        String message = "Custom SSO error message";
        SsoLoginException exception = new SsoLoginException(message);

        assertEquals(message, exception.getMessage());

        // Test with special characters
        String specialMessage = "SSO error: 特殊文字 & symbols <>\n\t";
        SsoLoginException specialException = new SsoLoginException(specialMessage);
        assertEquals(specialMessage, specialException.getMessage());

        assertEquals("value1", paramMap.get("key1"));
        assertEquals("value2", paramMap.get("key2"));
        assertEquals("value3", paramMap.get("key3"));

        // Test with special characters in keys and values
        value = "key.with.dots=value\nkey_with_underscores=value with spaces\nkey-with-dashes=value@#$%";
        paramMap = ParameterUtil.parse(value);
        assertEquals(3, paramMap.size());

            // Fallback to escaped plain text
            return escapeHtml(markdown);
        }
    }

    /**
     * Escapes HTML special characters for safe display.
     *
     * @param text the text to escape
     * @return HTML-escaped text
     */
    private String escapeHtml(final String text) {
        if (text == null) {
            return "";